UML is far more useful than TLA+, at least from the point of view of agile delivery projects.
Starting by at least with UML everyone, regardless of their role, can have some kind of understanding of what those diagrams are about, and UML covers most scenarios from software delivery product lifecycle.
Whereas TLA+ is mostly abstract code that after proving a specific algorithm is right, has to be manually ported to the actual software development stack being used, with the caveats a manual translation implies, and only applies to algorithm logic, nothing else.
UML has a place at my work, TLA+ will never get one.
Starting by at least with UML everyone, regardless of their role, can have some kind of understanding of what those diagrams are about, and UML covers most scenarios from software delivery product lifecycle.
Whereas TLA+ is mostly abstract code that after proving a specific algorithm is right, has to be manually ported to the actual software development stack being used, with the caveats a manual translation implies, and only applies to algorithm logic, nothing else.
UML has a place at my work, TLA+ will never get one.